Wind and Structures

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Application of numerical models to evaluate wind uplift ratings of roofs: Part II

  • Baskaran, A. (National Research Council Canada) ;
  • Molleti, S. (Department of Civil Engineering, University of Ottawa)
  • Received : 2004.02.01
  • Accepted : 2005.03.10
  • Published : 2005.06.25
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Abstract

Wind uplift rating of roofing systems is based on standardized test methods. Roof specimens are placed in an apparatus with a specified table size (length and width) then subjected to the required wind load cycle. Currently, there is no consensus on the table size to be used by these testing protocols in spite of the fact that the table size plays a significant role in wind uplift performance. Part I of this paper presented a study with the objective to investigate the impact of table size on the performance of roofing systems. To achieve this purpose, extensive numerical experiments using the finite element method have been conducted and benchmarked with results obtained from the experimental work. The present contribution is a continuation of the previous research and can be divided into two parts: (1) Undertake additional numerical simulations for wider membranes that were not addressed in the previous works. Due to the advancement in membrane technology, wider membranes are now available in the market and are used in commercial roofing practice as it reduces installation cost and (2) Formulate a logical step to combine and generalize over 400 numerical tests and experiments on various roofing configurations and develop correction factors such that it can be of practical use to determine the wind uplift resistance of roofs.

Keywords

References

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  2. Wind Uplift Behavior of Mechanically Attached Single-Ply Roofing Systems: The Need for Correction Factors in Standardized Tests vol.134, pp.3, 2008, https://doi.org/10.1061/(ASCE)0733-9445(2008)134:3(489)
  3. Calculating roof membrane deformation under simulated moderate wind uplift pressures vol.31, pp.3, 2009, https://doi.org/10.1016/j.engstruct.2008.10.013
  4. A novel approach to estimate the wind uplift resistance of roofing systems vol.44, pp.4, 2009, https://doi.org/10.1016/j.buildenv.2008.06.024